Vortex phase diagram in weakly pinned Rh₁₇S₁₅

Abstract

A vortex phase diagram of the strongly correlated superconductor Rh₁₇S₁₅ has been constructed via exploration of the anomalous variations in critical current density extracted from ac and dc magnetization measurements. The isofield in-phase ac susceptiblity data reveal the presence of multiple steps at different fields. The dc magnetisation hysteresis loops show the presence of a very broad fishtail commencing deep inside the mixed state and lasting upto H_c2. We have also analysed the scan rate dependence of the hysteresis width in the vibrating sample magnetometer data with a view to distinguish between the different possible order-disorder transformations in the flux line lattice.